fix(instrumentation-express): Finish spans after execution

[onurtemizkan]

Which problem is this PR solving?

Resolves: #2442

• TBD

Short description of the changes

• TBD

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.79%. Comparing base (3350583) to head (687c821).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2603      +/-   ##
==========================================
- Coverage   90.79%   90.79%   -0.01%     
==========================================
  Files         169      169              
  Lines        8059     8057       -2     
  Branches     1645     1644       -1     
==========================================
- Hits         7317     7315       -2     
  Misses        742      742              

Files with missing lines	Coverage Δ
...try-instrumentation-express/src/instrumentation.ts	98.56% <100.00%> (-0.03%)	⬇️

[github-actions]

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